COINCIDENCE OR PROPHECY? A GEOLOGICAL ANALYSIS OF JOHN MUIR’S FAMOUS ACCOUNT IN GLACIER BAY IN THE LATE 19TH CENTURY
A developing network of climate sensitive ring-width and blue intensity tree–ring chronologies along the Gulf of Alaska and within Glacier Bay National Park and Preserve aid our understanding of the climate, both locally and synoptically, at the time of Muir’s expeditions. His timing also coincided with the transition from the Little Ice Age into the modern era of secular warming. These tree-ring chronologies also assist with reconstructing the glacial and ecological history within Glacier Bay at the time of Muir, allowing for direct comparison with Muir’s personal notes and sketches. In his journal notes Muir reports that Muir Glacier was resting relatively stably on its morainal bank, but would soon retreat into deeper water due to calving. While his namesake glacier was in this stable state, it enabled Muir to explore Tree Mountain on the glacier’s Southeastern margin. His sketches of Tree Mountain depict young trees whose growth during this time is reflected by a series of cores taken from the location in 2011. John Muir’s famous account of his late 19th century visit to Glacier Bay was both influenced by climatological and geomorphic processes. However, the question remains if his observations were exaggerated by both the coincidental position and state of Muir Glacier in the tidewater glacier cycle and of warm intervals associated with decadal climate oscillations, or if they were deeply prophetic of a longer-term secular trend. It is possible then, that his account of Glacier Bay was most largely influenced by a coincidence of timing.